Abstract

The performance of a commercial optical contouring system is presented. The AMMON 2000, an optical casting system that is used to contour the bottom of the human foot for the podiatry industry, incorporates a phase-shifting fringe-projection profiler. The height profile data, z(x, y), measured with the instrument, are used to automatically design and surface a correcting orthotic. Data reduction software accounts for geometric distortions that are intrinsic to fringe projection topography when generated with a nontelecentric optical system. Contributions to the distortion that are due to the finite distance of the camera and projector exit pupils are detailed. By knowing the various parameters associated with the optical setup, as well as the position of a single reference point on the object, found by some other means, it is theoretically possible to transform the raw OPD data to the desired height contour, z(x, y), with absolute accuracy. In the AMMON 2000 the reference point is obtained by viewing the object at an angle that is nearly orthogonal to the projection axis.

© 1989 Optical Society of America